Light quenching is a unique opportunity to increase the resolution in fluorescence light microscopy. The resolution of a fluorescence light microscopy can be increased by quenching the excited molecules at the outer regions of the focused light spot, as has been shown in a theoretical study. For the practical development of such a microscopy the light quenching properties and their study are of essential interest. The goal of the present studies is to define and measure the amount of light quenching depending on the wavelength and intensity of the beams used. It will be of utmost interest to find dyes working in the IR regime since these dyes can easily be exploited in combination with the easy-to-use Titanium-Sapphire lasers. It is also interesting to study the lifetimes of the dyes in order to optimize the setup for maximum light quenching.